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131.
132.
Koenig A Roegler C Lange K Daiber A Glusa E Lehmann J 《Bioorganic & medicinal chemistry letters》2007,17(21):5881-5885
The vasoactive properties of 14 organic mononitrates were investigated in vitro using PGF(2alpha)-precontracted porcine pulmonary arteries. A surprisingly wide range of vasorelaxant potencies was observed (pD(2): 3.36-7.50). Activities showed to be highly sensitive to the molecular structure and the substituents at the molecular carrier of the nitrate group. A correlation between lipophilicity and vasorelaxant potency could not be recognized. 2-Nitrooxyethylammoniumnitrate (1) was found to be slightly superior to the high potency trinitrate GTN. 相似文献
133.
134.
Wilson R Gradstein SR Schneider H Heinrichs J 《Molecular phylogenetics and evolution》2007,43(1):270-282
With about 1000 species in approximately 90 genera, Lejeuneaceae are the largest family of liverworts and make up a large and important part of cryptogamic diversity in the humid tropics. Maximum parsimony, Maximum likelihood and Bayesian analyses of a dataset including four markers (rbcL, psbA, trnL-trnF region of cp DNA, nrITS region) of 134 accessions resulted in similar topologies that support the presence of four main lineages within Lejeuneaceae. Model-based analyses support a division of Lejeuneaceae into two lineages corresponding to the subfamilies Ptychanthoideae and Lejeuneoideae. The latter lineage splits into the tribes Lejeuneeae, Brachiolejeuneeae and the genus Symbiezidium. In contrast, the Maximum parsimony analysis resolves Brachiolejeuneeae and Symbiezidium in serial sister relationships to the remainder of Lejeuneaceae. Sporophyte characters support a split into two subfamilies as seen in the model-based analyses. Some deep nodes remain unresolved, possibly indicating a series of initial diversifications which occurred over a short time period. 相似文献
135.
Tribolium castaneum has telotrophic meroistic ovarioles of the Polyphaga type. During larval stages, germ cells multiply in a first mitotic cycle
forming many small, irregularly branched germ-cell clusters which colonize between the anterior and posterior somatic tissues
in each ovariole. Because germ-cell multiplication is accompanied by cluster splitting, we assume a very low number of germ
cells per ovariole at the beginning of ovariole development. In the late larval and early pupal stages, we found programmed
cell death of germ-cell clusters that are located in anterior and middle regions of the ovarioles. Only those clusters survive
that rest on posterior somatic tissue. The germ cells that are in direct contact with posterior somatic cells transform into
morphologically distinct pro-oocytes. Intercellular bridges interconnecting pro-oocytes are located posteriorly and are filled
with fusomes that regularly fuse to form polyfusomes. Intercellular bridges connecting pro-oocytes to pro-nurse cells are
always positioned anteriorly and contain small fusomal plugs. During pupal stages, a second wave of metasynchronous mitoses
is initiated by the pro-oocytes, leading to linear subclusters with few bifurcations. We assume that the pro-oocytes together
with posterior somatic cells build the center of determination and differentiation of germ cells throughout the larval, pupal,
and adult stages. The early developmental pattern of germ-cell multiplication is highly similar to the events known from the
telotrophic ovary of the Sialis type. We conclude that among the common ancestors of Neuropterida and Coleoptera, a telotrophic meroistic ovary of the Sialis type evolved, which still exists in Sialidae, Raphidioptera, and a myxophagan Coleoptera family, the Hydroscaphidae. Consequently,
the telotrophic ovary of the Polyphaga type evolved from the Sialis type.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
136.
Meegan MJ Barrett I Zimmermann J Knox AJ Zisterer DM Lloyd DG 《Journal of enzyme inhibition and medicinal chemistry》2007,22(5):655-666
A series of novel benzothiepin-derived compounds are described as potent selective modulators of the human estrogen receptor (SERMs). The objective of the study is to evaluate the antiproliferative effects of the compounds on human MCF-7 breast tumor cells. These heterocyclic compounds contain the traditional triarylethylene arrangement exemplified by tamoxifen, conformationally restrained through the incorporation of the benzothiepin ring system. The compounds demonstrated potency at nanomolar concentrations in antiproliferative assays against an MCF-7 human breast cancer cell line with low cytotoxicity. The compounds exhibited low nanomolar binding affinity for the estrogen receptor (ER) with some specificity for ERbeta, and also demonstrate potent antiestrogenic properties in the human uterine Ishikawa cell line. The effect of a number of functional group substitutions on the ER binding properties of the benzothiepin molecular scaffold is explored through a brief computational structure-activity relationship investigation with molecular simulation. 相似文献
137.
Barber Nicholas A. Sauer Nikki Krauss Jochen Boetzl Fabian A. 《Biodiversity and Conservation》2022,31(11):2857-2873
Biodiversity and Conservation - Semi-natural grasslands are biodiverse ecosystems that support many threatened species, but they require management interventions to maintain their habitat... 相似文献
138.
139.
Laura Morley Alan McNally Konrad Paszkiewicz Jukka Corander Guillaume Méric Samuel K. Sheppard Jochen Blom Georgina Manning 《Applied and environmental microbiology》2015,81(11):3641-3647
Campylobacter jejuni is a highly diverse species of bacteria commonly associated with infectious intestinal disease of humans and zoonotic carriage in poultry, cattle, pigs, and other animals. The species contains a large number of distinct clonal complexes that vary from host generalist lineages commonly found in poultry, livestock, and human disease cases to host-adapted specialized lineages primarily associated with livestock or poultry. Here, we present novel data on the ST403 clonal complex of C. jejuni, a lineage that has not been reported in avian hosts. Our data show that the lineage exhibits a distinctive pattern of intralineage recombination that is accompanied by the presence of lineage-specific restriction-modification systems. Furthermore, we show that the ST403 complex has undergone gene decay at a number of loci. Our data provide a putative link between the lack of association with avian hosts of C. jejuni ST403 and both gene gain and gene loss through nonsense mutations in coding sequences of genes, resulting in pseudogene formation. 相似文献